Congratulations on the 15 pounds!
I'm having a hard time picturing what yor're describing but it sounds like a good place to start would be moisturizing.
I have dry skin and it starts looking like alligator skin or like dried up patches of mud (I know my descriptions are terrible!
) So I moisturize like crazy whenever I dry off from my shower.
Another thing to look at might be your fat consumption. When we go on diets, sometimes we cut back on fats too much and our skin shows it. We need good fats (like salmon, avocados, olive oil, nuts etc) for nice skin and proper utilization of fat soluble vitamins. Most healthy eating plans recommend between 20 and 30% of your calories coming from good fats. It might be something to check?
If it's baby stretch marks, I've read that a dermatologist can treat them as long as they're still red and not yet faded to silver. If your fats are OK and you're moisturizing like crazy and you're still having problems, that should probably be your next stop.
Anyone have other ideas?